DUAL POWER The dual power supply of solar and y (includes one AA y) is what makes the desktop calculator work. Auto-off when you’re not using it about 10 minutes, to save more energy. CHECK & CORRECT FUNCTION The office calculator can calculate taxes quickly and easily. Auto replay and check function allows users to store, check, and correct up to 112 entries. The backspace key makes quickly correct of a single error. LARGE LCD DISPLAY 14 digits make the calculator useful for large calculations, suitable for office, school, market or home use that needs to make any sort of calculation. When you put the solar calculator on the desktop, the 30° large display is just opposite your sight, which makes it more clear than a straight display. BIG SENSITIVE BUTTON The three-color buttons help you recognize numbers and operational characters quickly and conveniently, the ergonomic big button gives a comfortable touch and good sensitivity performance. PREMIUM QUALITY Made with high quality this financial calculator is made to last years of constant use. We are getting customers who are extremely satisfied.